The vehicle pull (sideways) is a complex outcome of many
parameters in an automobile vehicle. This is mainly due to
steering, suspension, brake, wheels and chassis parameters. The
road conditions like road camber also plays an important role in
vehicle pull behavior. All efforts are put in design and
manufacturing processes to maintain controlled vehicle pull in
normal driving condition. Even though normal vehicle pull seems to
be in acceptance limit (subjectively), its intensity increases many
folds at the time of harsh braking. In these kind of panic
situations where driver firmly holds on the steering wheel, it is
expected that the vehicle should stop without deviating too much
sideways from its intended straight line path to avoid any kinds of
accidents.
This work is an outcome of systematic study carried out to
understand the root cause of brake pull as a field complaint on
current production vehicles and adopting best possible solutions to
minimize the brake pull. This paper presents an experimental study
and comparison of contribution of two basic kinds of steering
linkage layouts type 1 and type 2 (detailed descriptions followed
in section 1) on RHD (right hand drive) vehicle, used in
front-wheel-steered vehicles having independent suspension on
vehicle pull and brake pull. Brainstorming resulted in some
critical hypothesis about possible contribution of these two basic
layouts on vehicle pull while braking which was further supported
by primary CAE (computer-aided engineering) analysis using
classical approach (ADAMSĀ® Model). Same has been validated through
experimental tests also. While both of these mechanisms are widely
used by different automobile OEM's (original equipment
manufacturers) as they fulfill most of the design requirements of
steering systems, the in-depth analysis of contribution of these
two layouts on brake pull surely puts one on top of the other. The
work helps in understanding the finer details of steering linkage
design requirements and provides design guidelines to deliver
better product through improved safety and better customer
satisfaction.